Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Grand Forks ND
1225 PM CDT sun Sep 21 2014

Update...
issued at 947 am CDT sun Sep 21 2014

Clouds will continue to be the main challenge for today.
The convective temperature will remain low this afternoon due to
higher 925mb-850mb moisture. Increased cloud cover and extended
into the early evening hours east of the valley. This also led to
decreasing maximum temperatures a bit. Locations west of the valley should
also develop cumulus by late morning...but coverage should be more
scattered and then eventually erode from west to east (as ridging
builds from the west).

&&

Short term...(today through monday)
issued at 359 am CDT sun Sep 21 2014

Upper level trough over California forecast to move into the northern plains
by Tuesday. Precipitable water rises over an inch by Tuesday and approaches
an inch an a quarter to an inch and a half by 84 hours. Despite
impressive precipitable water, instability remains on the west side
of the trough axis. So mostly warm advection precipitation is expected for
Tuesday through Wednesday night. Will go for showers with isolated thunder.

For this morning water vapor loop indicated a short wave over WI and
another secondary lobe over northern Minnesota. Light showers were
occurring over the far northeastern zones. Will add low probability of precipitation for
this morning over the far east zones. Model soundings indicate temperatures
increase above 850 hpa and create a cap aloft by 7 PM CDT today.
Temperature continue to increase aloft through Monday afternoon. An inversion
lowers to just off the surface by Monday afternoon. Will go cooler for
today.

Long term...(monday night through saturday)
issued at 359 am CDT sun Sep 21 2014

For Wednesday through Sunday...models in good agreement. Some
differences Wednesday as a 500 mb short wave trough lifts northeast
from Wyoming and Colorado into eastern North Dakota Tuesday night
into early Wednesday. Precipitation with this system is mostly on the
south and east side of the this wave and pretty limited. 00z European model (ecmwf)
remains a bit wetter than the 00z GFS. Maintained chance
probability of precipitation...highest in Minnesota forecast area. Thereafter a deep 500 mb
trough moves into the West Coast and a 500 mb ridge builds into the
northern plains Thursday-Sat with warm and dry weather. 00z GFS breaks down
the ridge a bit faster in the late period than the European model (ecmwf) and in many
cases the slower so line is best. All blend probability of precipitation followed the drier
solution. Temperatures will rise to well above normal levels late
week.

&&

Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1225 PM CDT sun Sep 21 2014

Looking for scattered-broken cumulus this afternoon...thinning out first at
kdvl. Kgfk/kfar should thin out by late afternoon with kbji/ktvf
likely taking longer. North-northwest winds at 5 to 10 knots should become
light tonight.

&&

Fgf watches/warnings/advisories...
ND...none.
Minnesota...none.
&&

$$

Update...tg
short term...hoppes
long term...Riddle
aviation...godon

National Weather Service Glossary of Abbreviations